ABSTRACT
Chapter 9 details the electrolyte abnormalities experienced by those who purge, as well as explaining why patients may develop severe edema, or retention of fluid, when they stop purging. Many patients who purge have poor experiences in hospital emergency departments. Low potassium levels, or hypokalemia, can cause muscle weakness, intestinal dysfunction, and cardiac arrest. A prolonged QT interval on the EKG is a risk factor for the deadly rhythm torsades de pointes. The serum bicarbonate can be used as a proxy for a patient’s degree of volume depletion, or dehydration. A high bicarbonate level predicts edema after purging cessation. A low serum sodium level is called hyponatremia, and the chapter reviews how to determine its cause and treatment. The three main etiologies are volume depletion, inadequate caloric intake, and the Syndrome of Inadequate Anti-Diuretic Hormone secretion (SIADH). A high serum sodium level, hypernatremia, may arise from restriction of fluids or from diabetes insipidus, where the pituitary gland fails to make sufficient anti-diuretic hormone. Pseudo-Bartter syndrome, or secondary hyperaldosteronism, arises during chronic volume depletion and is the cause of severe edema upon purging cessation. Key treatment points are discussed.
